Open the Compass in the Sajda app. Place your device parallel to the ground (e.g., on a table). The needle should point in one direction and stop. Rotate your device a few times around its axis and then place it back. If the needle points in the same direction, the Compass is working.

If you are using the Compass in an area with a lot of metal or electromagnetic interference, the data might be inaccurate. Also, if your device doesn't have a built-in geomagnetic sensor, the Compass won't work.